1. Field of the Invention
Various embodiments of the present invention relate to an infrared image sensor, and more particularly, to a readout integrated circuit (ROIC) for an infrared signal applicable to an uncooled infrared image sensor such as a microbolometer.
2. Description of the Related Art
An infrared thermal imaging system is an apparatus able to obtain an image of an object using emitted radiant energy, and has a wide range of military, industrial, medical, and other applications.
An infrared thermal imaging system may include, for example, an optical system, an infrared detector, a readout integrated circuit (ROIC), a signal processing circuit and the like. In developing an infrared thermal imaging system, a material for the infrared detector, a micro-machining process, a design of the readout integrated circuit for processing an electrical signal output from the infrared detector, a monolithic process for connecting the infrared detector to the readout integrated circuit, a packaging process and the like are all essential elements.
In particular, in order to develop a high-resolution readout integrated circuit (ROIC) for an infrared signal, a technique for designing a high-integrated yet low-power circuit, satisfying the factors of the characteristics of the detector, a signal operation range, a detection rate, noise characteristics, the size of cells, power consumption and the like, is essential.
For example, a readout integrated circuit for an uncooled infrared image sensor such as a microbolometer may include a circuit for performing current skimming within a pixel for a lower power operation.